1. Field of the Invention
The present invention relates to roll-to-roll type apparatuses for forming thin film patterns, and more particularly, to a roll-to-roll type apparatus for forming a thin film pattern that forms a desired thin film pattern on a sheet running between rolls.
2. Description of the Related Art
In general, as digital electronic products have been reduced in size and increased in functionality, various types of passive components have correspondingly been reduced in size, thickness, and weight while functions of the passive components have been upgraded. Especially, a large number of capacitors are used in portable small electronic products, such as camera phones, DMB phones, and navigations. There is growing need to increase the capacity and functionality of the capacitor while the capacity needs to be formed of multilayered ultra-thin films.
However, the existing screen printing method is limited when achieving high-capacity capacitors within the same chip size. In order to overcome this limitation, various kinds of methods have been attempted, and among them, there is a roll-to-roll process. Significant consideration has been given to this roll-to-roll because it is more suitable for mass production than an existing batch type process when implementing a display or a device on a flexible substrate.
The roll-to-roll type apparatus for forming a thin film has advantages of mass production because a process is performed while a sheet is continuously transferred, but it is difficult to form a pattern necessary to manufacture a device. There is a method of forming a layer on a sheet wound in a roll, cutting the sheet, and arranging the cut sheet. However, since this method may not allow mass production, it is difficult to use the method when repeating the formation of a thin film pattern.
To overcome difficulties, there is a method of forming a desired pattern on a sheet running between rolls by using a roll type mask having various patterns as a mask. However, it is difficult to make tight contact with a deposition object in a roll-to-roll process using the roll type mask. Therefore, it is difficult to ensure a precise thin film pattern. When the roll type mask is used, other devices such as a driving roll and a guide roll to move the mask are required.
Further, when any one of the various patterns of the roll type mask is damaged, the repair of the roll type mask is difficult.
Therefore, there is a need for a technique that effectively forms a thin film pattern in a roll-to-roll process.